Question

此代码将正常执行，但foreignkey记录将不会保存在数据库中：

new_org, created = models.Organization.objects.get_or_create(symbol = row['Symbol'], batch=batch_id)
new_org.industry, created = models.DictIndustry.objects.get_or_create(value=row['industry'], batch=batch_id)
new_org.sector, created = models.DictSector.objects.get_or_create(value=row['Sector'], batch=batch_id)
new_org.save()
print(new_org.__dict__)

输出已分配了industry和sector：

{'_state': <django.db.models.base.ModelState object at 0x1142d0748>, 
'id': 3152, 
'date_created': datetime.datetime(2019, 2, 7, 21, 36, 55, 883816, tzinfo=<UTC>), 'date_updated': None,
'generation': 1,
'batch': 0,
'symbol': 'DDD',
'industry': <DictIndustry: Computer Software: Prepackaged Software>,
'sector': <DictSector: Technology>}

但是数据库将没有这些记录：

  id  |         date_created          | date_updated | generation | batch | symbol | industry_id | sector_id 
------+-------------------------------+--------------+------------+-------+--------+-------------+-----------
 3152 | 2019-02-07 16:36:55.883816-05 |              |          1 |     0 | DDD    |             |

industry和sector的记录都可以很好地沉入数据库（postgresql）。

我怀疑这与我对模型进行编码的方式有关，但是我无法发现任何可能破坏它的东西。 PostgreSQL是否有任何特定原因可能导致这种情况？

class BaseModel(models.Model):
    date_created = models.DateTimeField(auto_now=True)
    date_updated = models.DateTimeField(null=True, blank=True)
    generation = models.IntegerField(default=DATA_GENERATION)
    batch = models.IntegerField()

    class Meta:
        abstract = True


class AttributeBase(BaseModel):
    source = models.CharField(max_length=16, blank=False, null=False)

    def __str__(self):
        if hasattr(self, 'value'):
            return self.value
        raise NotImplementedError("value field not implemented for this model and it should have been")

    class Meta:
        abstract = True
        unique_together = ('source', 'parent', 'value', 'generation')


class DictBase(BaseModel):
    value = models.CharField(max_length=128, unique=True)

    class Meta:
        abstract = True

    def __str__(self):
        if hasattr(self, 'value'):
            return self.value
        raise NotImplementedError("value field not implemented for this model and it should have been")


class DictSector(DictBase):
    pass


class DictIndustry(DictBase):
    pass


class Organization(BaseModel):
    symbol = models.CharField(unique=True, max_length=12, null=False, blank=False)
    sector = models.ForeignKey(DictSector, on_delete=models.DO_NOTHING, null=True, blank=True)
    industry = models.ForeignKey(DictIndustry, on_delete=models.DO_NOTHING, null=True, blank=True)

    def __str__(self):
        return self.symbol

Answer 1

这与django无关，并且django可以正常工作。以防万一它可以帮助某人。如果您在Jupyter之类的笔记本中运行与Django相关的代码，请不要忘记重新加载内核以随身携带您正在制作的模型中的更改。

（我尝试自动重新加载，但对我来说效果不佳）。

从get_or_create结果分配

1 个答案: